Oct 16 2008

drivers/misc: Use DIV_ROUND_UP 

Author: Julia Lawall <julia@diku.dk>

The kernel.h macro DIV_ROUND_UP performs the computation (((n) + (d) - 1) /
(d)) but is perhaps more readable.

An extract of the semantic patch that makes this change is as follows:
(http://www.emn.fr/x-info/coccinelle/)

// 
@haskernel@
@@

#include 

@depends on haskernel@
expression n,d;
@@

(
- (n + d - 1) / d
+ DIV_ROUND_UP(n,d)
|
- (n + (d - 1)) / d
+ DIV_ROUND_UP(n,d)
)

@depends on haskernel@
expression n,d;
@@

- DIV_ROUND_UP((n),d)
+ DIV_ROUND_UP(n,d)

@depends on haskernel@
expression n,d;
@@

- DIV_ROUND_UP(n,(d))
+ DIV_ROUND_UP(n,d)
// 

Signed-off-by: Julia Lawall 
Cc: Jack Steiner 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 

---
 drivers/misc/sgi-gru/grukservices.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
 
diff --git a/drivers/misc/sgi-gru/grukservices.c b/drivers/misc/sgi-gru/grukservices.c
index dfd49af..08d29cd 100644
--- a/drivers/misc/sgi-gru/grukservices.c
+++ b/drivers/misc/sgi-gru/grukservices.c
@@ -466,7 +466,7 @@ int gru_send_message_gpa(unsigned long mq, void *mesg, unsigned int bytes)
 	STAT(mesq_send);
 	BUG_ON(bytes < sizeof(int) || bytes > 2 * GRU_CACHE_LINE_BYTES);
 
-	clines = (bytes + GRU_CACHE_LINE_BYTES - 1) / GRU_CACHE_LINE_BYTES;
+	clines = DIV_ROUND_UP(bytes, GRU_CACHE_LINE_BYTES);
 	if (gru_get_cpu_resources(bytes, &cb, &dsr))
 		return MQE_BUG_NO_RESOURCES;
 	memcpy(dsr, mesg, bytes);

qlambert